R&D Report 1965-18 : Recent work on the effects of reflectors in concert halls and music studios. T. Somerville, C.L.S. Gilford, N.F. Spring, R.D.M. Negus
A common complaint in many modern concert halls is poor tonal quality. It has been suspected that this effect was due in large measure to the use of reflecting canopies and other large reflecting surfaces. Furthermore, vertical shifts in the apparent position of the sound source are often observed. This report describes experiments to investigate both these effects which are shown to be due to the use of directional reflexion.